Lubricating system for loom letoffs



April 29, 1952 w. s. sNow LUBRICATING SYSTEM FOR LOOM LETOFFS Filed Jan. 26, 1951 INVENTOR WARREN $.SNOW

ATTORNEY Patented Apr. 29, 1952 SYSTEM FOR LOOP/I LllI'IQI IfS Warren S. Snow, Worcester, Mass, assig nor to Crompton & Knowles Loom Works, Worcester, Mass, a corporation of Massachusetts Application January 26, 1951, s ria 207,913 Claims. (01. 139-}19) Thi invention relates to improvements in loom letofli'mechanism and it is the general object of the invention to provide simple means by which the mechanism can be lubricated by forces arisin'g'from' operation of the let/off mechanism during' loom operation.

A form of. letoff. mechanism which has gone into general use employs a Worm gear fixed with respect to the warp beam meshing with a worm carried by a weighted casing or the like. The warp beam and worm wheel turn progressively in a forward direction to provide warp for the weavingfope'ration; butfthe operation of the harness frames and the beat-upjof the lay cause a temporary'iorward motion of the warp. The weight exerts 'arearward. force on the warp beam tending to turn it a reverse direction to move the warp rearwardly after beat-up. The harness frames and lay operate regularly, and together with theiweighted member produce oscillation of both the warp beam and the weighted member. This oscillation is dampened but not completely eliminated. by a dashpot or the like.

It is'an important object of the present invention t'o, providejmeans associated with the dashpot. for lubricating the worm and worm wheel so that, these partscf theletofi mechanism may be. more) responsive to the means which effec'ts turning of the worm in order to effect a step-back of ;the weighted member with respect to "the warp beam.

"The means for turning the worm includes a form of clutch and rack and rack gear, the rack being operated'by some part moving in time with the'loom and the rack gear turning one of the clutch members to cause the other clutch member to turn'th'e' worm relatively to the worm wheel. It'isa further object of the invention to lubricate this turning, means for the worm by oil derived from the dashpot. and directed against the means incident to oscillation of the Warp beam as the weaving process, continues.

The mechanism to be lubricated is ordinarily above the dashpot and in order that lubrication may start immediately upon operation of the loom it is a further object, of the invention to provide a valvewhich will prevent return of. oil from the point offlubricati'on to the, dashpot during periodsof. idleness of the loom.

With these and other 'objects'in view which will appear "as the description proceeds, the invention resides in the "combinationand arrangement of parts'he'r'einafter described and set forth.

"Inth'e, accompanying drawings; wherein a converiient embodiment ofithe'invention is set forth,

i 1 isa sideelevation i a toi. a oom S ing a letofieguipped with the present invention,

Fig. 2 is. an enlarged longitudinal section through the dashpot and parts associated therewith online 2 2, Fig. 1,

F .3. s. a lar ed ve t qa detai d section on line 33, Fig. 2, showing the valve which prevents return of oil from the point of. lubrican. t t dashppt E is. an n ar ed. vert ca sec i on n 4; F 3.,

i 5: is an en ar ed vert a sect n line 5 5, Fig. 2 showing the piston in part of the a hp t.

6 s an n ar d h rizonta ct on line F show n he ball. a e reta n r. and t l e ers n. he ow r art o th p on,

Big. 7 is an enlargedhorizontal section on line fie- F andv Fig. 8 is a vertical section on line 8-8 Fig. 7.

R rrin o Fig. 1 the. 09m rame I s pp r a lay 2 which is reciprpc ated b aclrwardly and forwardly by connectors 3 driven by the top or crank Shaft 4, The lay has a reed 5 which effects beat-up at the fell 6 of the cloth C of weft threads laid by a shuttle S. The beat-up of the reed occurs once for each flight of the shuttle and has the effect of momentarily increasing the tension of the warp threads W when engaging the fell 6.

he w re t ad-s ar v on o l b h ess frames two of, which areshown at 1 and 8. The mechanism for raising and lowering these harness frames is not set forth herein but. operates to sepa ate the W rp h s, t t Sheets which define the Warp shed 9. When the harness frames orm. a Wa p: hed th r is a ta y increase inthe tension of, the warp threads. It will thus be seen that due to the back and forth reciprocation of the lay 2 and operation of the shedding mechanism represented herein by the harness. frames 1 vandlfithe warp threads are subjeot to a varying tension.

The warp'threa'ds extend. rearwardly and are wrapped a'r'ound'a warp beam to on a shaft ll. Theend'of the beam shown in Fig. '7. is provided with a member [2 having an integral tube it through which the shaft ltl extends. The tube i3 is supported? by. a ball bearing I14 mounted on the upper end of a stand I5 held. in vertically adjusted' position on a'frame l5. extending'rearwardly from the loom.

Surrounding the tube. I3. is a worm gear member'2Q heldto the member 12 as by a'set screw 21." A set, screwfzlin a. collar 23. surrounding a 3 split extension of the tube I3 is set against the shaft I I so that the latter, the member l2 and the worm wheel member 26 turns as a unit with the warp beam I6. Collar 23 is secured to tube I3 by a set screw 24.

A hollow casing 36 is mounted to turn on the worm wheel member 26 concentric with the axis of the warp beam and shaft II and has secured to the rear part thereof, the left in Fig. 1, an arcuate casting 3| to the upper end of which a cable or rope 32 is held as at 33. The lower end of the cable supports a weight 34.

The casing 36 has journaled therein a shaft to which a worm 36 is keyed as at 31. The worm 36 meshes with the worm wheel proper indicated at 33 forming part of the member 26. A bearing 46 between the casing 36 and the lower end of the worm 36 limits movement of the latter downwardly with respect to the casing, as will be apparent from Fig. 8. The weight 34 tends to turn the casing 36 in a counter-clockwise direction as viewed in Figs. 1 and 8 and the casing acting through the bearing 46 and the worm 36 tends to turn the worm wheel and the beam in a counter-clockwise direction so as to create tension in the warp threads.

As weaving continues the warp beam turns in a clockwise direction as viewed in Fig. 1 in order to supply weft for the cloth C and this effects clockwise movement of the casing against the action of weight 34, lifting the latter. In order to step the casing backwardly or in a counterclockwise direction as viewed in Fig. 1 with respect to the beam, means shown more particularly in Figs. 1 and 8 is provided to turn the worm. A clutch member is keyed as at 46 to shaft 35 and meshes with a second clutch member 41 slidable along shaft 35 This second clutch member is formed in part as a gear designated at 48 to mesh with a rack 49 slidable horizontally in the casing 36.

The support I5 has an operating lever 50 pivoted thereon as at 5| and a rod 52 extending forwardly from the lever to an eccentric 53 on the crank shaft 4 effects rocking of lever 56 during loom operation. The lever has a wing 54 for engagement with the rack 49 when the casing has been turned a sufiicient angular distance in' a clockwise direction as viewed in Fig. 1 to bring the rack within the range of operation of the wing '54. When this happens clutch member 41 will be turned to effect turning of the clutch member 45 keyed to shaft 35 and the resultant turning of the worm 36 will be in such direction as to permit the casing and the parts carried by it to be moved in a reverse direction, or counterclockwise as viewed in Figs. 1 and 8 for a step back motion with respect to the warp beam. The rack 49 tends to move toward the wing 54, but when the casing has its reverse motion the rack will be moved to the left, Fig. 1, out of the range of the reciprocating wing 54 where it will remain until it is again moved forwardly for a repetition of the operation already described. In this way the casing is stepped back to keep the weight 34 rearward of the beam to maintain tension on the warp threads as the warp beam turns to supply warp for the weaving operation. During the time the rack is out of therange of action of the wing the worm and its worm wheel will be stationary with respect to each other andif there is any considerable force exerted by the weight 34, as may be'necessary with certain types of warps, the lubrication between the worm and its wheel is squeezed out of place so as to increase the frictional resistance to turning of the worm with respect to the worm wheel.

During loom operation, the periodic forward motion of the warp due to action of the lay and shedding mechanism, and the subsequent rearward motion due to weight 34 as the-lay moves away from the fell, causes the beam and the weighted casing to oscillate. Means to dampen this oscillation includes an oil cylinder 55 secured as at 56 to the support I5 and having mounted for reciprocation therein a piston 51 at the lower end of a rod 58 the upper end of which is connected as at 59 to the arcuate casting 3|. The cylinder contains oil designated herein at L.

The matter thus far described may be substantially the same as that shown in prior patent to Payne N 0. 1,803,143 to which reference may be had for a more complete description of the operation of the letofi.

In carrying the present invention into eifect provision is made for enabling reciprocation of the piston5'I in the cylinder 55 to lubricate parts of the letoff mechanism. A fitting is screw threaded into the lower part of the cylinder 55 and has a flexible preferably rubber or neolite hose clamped thereto as at 61. Fitting 65 has a passage or bore 68 the left end of which as viewed in Fig. 3 is provided with a valve seat 69 for a ball valve I6. The seat has a port ll through which oil can pass from the cylinder to the in terior of the hose 66.

A ball trap 12, see Fig. 4, is located at the right end of the passage 66, Fig. 3, to limit travel of the ball within the fitting and has openings 13 which permit oil to pass around the ball when the latter is at the right end of the passage 63. The tube 66 extends upwardly and in the present instance is attached to a Y fitting I5 one branch 16 of which is for the worm and worm wheel and the other branch 71 of which is for the turning means for shaft 35 and worm 36. The branch I6 is connected to a fitting 86 tapped into the casing 36 and provided on the interior thereof with a reducer iii the bore of which is directed toward the point of mesh between the worm and the worm wheel. Similarly, the branch TI is attached to a hose 83 leading to a fitting 84 similar to fitting 86 but tapped into the casing 36 in a position so that it can direct oil against the upper clutch member 46, see Fig. 8. This fitting 84 may be provided with a reducer 65 similar to reducer 8 I.

The piston has screw threaded in the under side thereof a fitting 96 having a passage or bore 9| at the upper end of which is a valve seat 92. The lower end of the fitting is provided with a trap or stop 93 for a ball valve 94 movable in the passage 6i. The trap 63 may be provided with bleeder ducts 95, see Fig. 6, which afiords communication for oil from that part of the cylinder below the piston with the passage 9| and through the valve seat 92 to the part of the cylinder above the piston.

The cylinder may have a bell shaped upper end 96 into which is tapped a fitting 91 connected to the lower end of a return tube 68 the upper end of which is attached to a fitting 99 communicating with the interior of the casing 36. The latter is made substantially oil-tight by a plate I66, which as shown in Fig. 7, is secured to the casing as by a screw I 6| so that the worm wheel 38 turns within a substantially closed compartment or space designated at I62 to the bottom of which oil will drip and thence through the tube 98 back to the bell 96.

In operation, the piston 51 will be moved downwardlyiin the. cylinder 55 due to action of the Weight 34 when there is a temporary slackening of. the tension of the warp thread, and as the piston movesdown the ball valve fi lwill rise in the boreQI against the valve seat 92 to prevent flow of. oil upwardly from the cylinder through the piston. This exerts a force on the oil moving it through the port H and bore 68 and through the bleeder by-pa'ss 13 into the tube 66, thereby raising the columnof oil in the tube 66 and directing oilthrough the reducers 8i and 85 against their respective mechanisms to lubricate them.

When'the piston 51 rises in the cylinder due to a temporary increase in the tension of the warp threads 'atbea't iip of the lay or warp shed opening the ball 10 will move to the left, Fig. 3, against the seat 69 to prevent return of oil from the hose 66 to the cylinder 55, thereby maintaining the column of oil in the hose 6%. During this upward motion of the piston the ball 94 will be in low position, but oil'can pass through the bleeder passages 95 downwardly from the bell 96'jintlo the lower part of the cylinder. Any excess" ofoil provided by the lubricating system will pass out of the bottom of the casing into the bell- 96 and be re-used for lubricating purposes as the loom continues to run.

While provision is shown herein for lubricating both the worm and worm wheel and also the means for turning the worm, lubrication of the latter may be omitted, but it is desirable to lubricate the worm and worm wheel since considerable forceis exerted between these two parts and their engaging surfaces should be kept lubricated.

From the foregoing it will be seen that the invention sets forth simple means for lubricating parts of a letoff mechanism by a dashpot which serves to dampen oscillation of the warp beam. The piston 51 on its downward stroke causes oil to issue from the reducers BI and 85 against their respective mechanisms, and when the piston rises in the cylinder 55 the ball valve 10 will prevent return of oil from the tube 65 to the cylinder, thereby maintaining a column of oil in the tube so that lubrication will start immediately upon resumption of weaving after a period of idleness on the part of the loom. While a specific form of letofi' mechanism has been shown the invention is not necessarily limited to such a mechanism but is useful wherever the letoff operation has some part which oscillates and has other parts requiring lubrication. The invention can be readily applied to letoffs now in use with the addition of very little more oil than that required for the dashpot. No additional means, such as a pump, is required to effect circulation of oil through the system and this circulation starts immediately upon resumption of weaving and stops as soon as the loom is brought to rest.

Having thus described the invention it will be seen that changes and modifications of the foregoing specific disclosure may be made without departing from the spirit and scope of the invention.

What is claimed as new is:

1. In a loom having a warp beam turning progressively during loom operation in a direction to supply warp for the Weaving operation of the loom, loom operated means periodically increas ing warp tension and acting through the warp to turn said beam in said direction, weighted means effecting reverse turning of the beam, said loom operated and weighted means effecting oscillation of the beam during loom operation, gearing operatiiiely connectingisaid beam, andTweig'hted means normally causing the? beam and weighted means to oscillate in unison but effective incident to mom operation to reverse the weighted means relatively'to the beam, a dashpot including a cylinder for oil'anda piston therein operatively connected to the weighted meansfand a lubrieating. system for said gearing connected to said cylinder and operative due to movement of the piston 'i n'sa'id cylinder incident to oscillation of said ivei'ghtedmeans to supply oil from the cylinder? to said ge tlillg.

In a loom having a warp beam turning progressively in a given direction to supply warp for thewea'ving operation ofthe'loom, means tending return thefbeam 'in' the opposite direction, geariiigtprauveiy connectin the means" to the team-"166m operated mechanism cooperating with "tdefieizt' oscillations of the beam s'dui'ing loom operation, a dashpot in clfiding'a cylinder for oil and a piston therein otermtely'eern'eaea to" the'means to dampen saiatseuiaabns; and a lubricating system conid cylinder operative to lubricate said to movement of'said piston in said cylinder incident'to, said oscillations.

'31 The structure set forth in claim 2 wherein the lubricating system includes a return for oil from said gearing to said piston. v

4. The structure set forth in claim 2 wherein the lubricating system includes a tubular member leading from the cylinder to said gearing and a valve preventing return of oil from said tubular member to said cylinder.

5. The structure set forth in claim 2 wherein a casing above said cylinder incloses said gearing and the lubricating system includes a gravity return for oil from the casing to the cylinder.

6. The structure set forth in claim 2 wherein a casing above said cylinder incloses said gearing and the lubricating system includes a tubular member leading from the cylinder to the casing to feed oil for lubricating said gearing and a check valve to prevent return of oil from the casing to the cylinder through said tubular memher.

'7. In a loom having a warp beam turning progressively in a given direction to supply warp for the Weaving operation of the loom, a worm gear secured to and turning with the beam, weighted means coaxial with and mounted for rotation relative to said beam, worm means rotatable on said Weighted means meshing with said worm gear and normally causing said weighted means and beam to move angularly in unison, means to rotate said worm on .said

Weighted means to eiiect angular movement of the weighted means relative to the beam in a direction opposite to said given direction, loom operated means cooperating with the weighted means causing oscillation of said beam and weighted means during loom operation, and a lubricatin system having a part connected to said weighted means efiective due to said oscillation of the latter to lubricate said worm means.

8. In a loom having a lay and a warp beam turning progressively in a given direction to supply warp for the weavin operation of the loom, a worm gear secured to and turning with the beam, weighted means coaxial with and mounted for rotation relative to said beam, worm means rotatable on said weighted means and meshing with said worm gear, mechanism'to turn the worm means to effect rotation of the Weighted means relative to the beam and worm gear in a direction opposite to said given direction, the lay cooperating with said weighted means and worm and worm gear causing oscillations of the beam and weighted means during loom operation, and a lubricating system having a part connected to said weighted means effective due to said oscillations to lubricate said worm means during loom operation.

9. In a loom having a warp beam turning progressively in a given direction to supply warp for the weaving operation of the loom, a worm gear secured to and turning with the beam, weighted means coaxial with and mounted for rotation relative to said beam and including an inclosed casing within which said worm gear is located, worm means rotatable on said weighted means and meshing with said worm gear, mechanism to turn the worm means to efiect rotation of the weighted means relative to the beam and worm gear in a direction opposite to said given direction, means including a loom operated part cooperating with said weighted means and worm and worm gear causing oscillations of the beam and weighted means during loom operation, and a lubricating system connected to the interior of said casing having a part connected to said weighted means efiective due to said oscillations to lubricate said worm means during loom operation.

10. In a loom having a warp beam turning progressively in a given direction to supply warp for the weaving operation of the loom, means tending to turn the beam in the opposite direction, mechanism operatively connecting said means and beam effecting movement of the means relative to the beam in a direction opposite to said given direction, a lay cooperating with said means and mechanism to cause oscillation of said means during loom operation, and a lubricating system operative due to said oscillation of said means to lubricate said mechanism.

WARREN S. SNOW.

REFERENCES CITED The following references are of record in the.

file of this patent:

' UNITED STATES PATENTS Marcy Aug. 21, 1951 

